In a stringed musical instrument, such as a guitar, the strings extend unsupported between a first critical point usually formed by the nut where the neck joins the head and a second critical point usually formed by the bridge positioned on the body. The strings are anchored at one end on a portion of the instrument known as the tailpiece, strung over the bridge and the nut on the head of the instrument and in conventional instruments anchored on the other end to the tuning pegs where an untensioned string is tensioned and adjusted to a tuned condition. The second critical point is formed by a part of the bridge or by a part of a combined bridge and tailpiece structure. Traditionally, the size of the bridge elements are quite small so as to create a clearly defined single point of contact between the string and the bridge element. It is between these two points that the string length is determined. This is sometimes referred to as the scale length. Adjusting the relative distance between the first and second critical points is called harmonic tuning. Some bridge structures have individually adjustable bridge elements for each string. Often the typical construction of the strings, particularly for guitar and bass, have a plain end and a “ball end” in which a washer-like addition is wrapped by the string itself as a means to help in securing the string to the instrument on the tailpiece. The wrapping is typically thicker than the rest of the string so that the wrapping is substantially inextensible. The wrapping usually extends for at least a ½″ towards the plain end and as such the tailpiece structure must insure that the wrapping does not extend over the second critical point when arranged on the instrument. Fine tuning has been a long standing problem for stringed musical instruments. In the Proelsdorfer U.S. Pat. No. 2,304,597, string tensioning devices placed on the tailpiece for fine tuning the pitch of the strings of violins, guitars and the like, were disclosed, however such pitch adjustment is quite limited in range and designed to offer the tuning of the strings a minor adjustment of pitch after the general tuning is achieved with the tuning pegs on the head of the instrument which first provides the means for raising and adjusting the tension of the strings to pitch from an untensioned condition.
It is known to those skilled in stringed musical instrument design and construction that various tremolos have been proposed and utilized for varying the tension of all the strings simultaneously for the purpose of creating a tremolo sound. Further, it is known to those skilled in the art that there are a great many commonly used names for such devices, such as tremolo, tremolo device, tremolo tailpiece, tremolo bridge, fulcrum tremolo, fulcrum tremolo bridge, fulcrum tremolo tailpiece, fulcrum tremolo bridge-tailpiece, vibrato, vibrato bridge, vibrato tailpiece, vibrato bridge tailpiece, etc.
In one specific species, known as the fulcrum tremolo, Fender U.S. Pat. No. 2,741,146, shows and provides a tremolo device which incorporates a novel bridge structure which incorporates the tailpiece and is commonly known to specifically provide the anchoring means for the strings. The bridge plate is also known as the base plate. The base plate upon which the individual bridge elements are adjustably secured has a beveled ridge portion which is secured to the instrument body by six screws for permitting pivotal movement about a fulcrum axis which varies the tension on the strings and produces the desired tremolo effect. The tailpiece is integrated into a spring block descending from the base plate into a cavity within the instrument body. Further, the bridge and the tailpiece both move together as the tremolo device is pivoted. The ball ends and wrapping of the strings are anchored into the recesses in the end of the string block furthermost from the base plate. The strings being threaded through bores individual to each string over two inches in length within the spring block continuing out through the bottom of the base plate and over the bridge elements towards the nut. A singular aspect of the fulcrum tremolo is that the harmonic tuning is upset as the device is pivoted.
Typically, when a fulcrum tremolo pivots about its fulcrum axis, counter springs are utilized to counteract to pull of the strings. Counter springs are usually connected to the body of the instrument at one end and to an attachment means on the bottom of the tremolo at the other end. One of the most troublesome problems with prior art has been maintaining the initial tuning at proper playing pitch. When a musician plays on the sting there is usually some kind of string stretch over time that results in the overall tuning going out of balance. Similarly, the use of the tremolo itself may also introduce string stretch. Further, various factors such as the changes in the humidity of the atmosphere causing the wood in the neck and/or body of the instrument to swell often create subtle distortions in the instrument's geometry which would then in turn disturb the equilibrium point between the tension of the strings and the tension of the counter springs and then as a consequence disturb the initial position. Initial position refers to a specific equilibrium point between the tension of the strings and the tension of the counter springs at the intended tuned pitched condition of the strings. Often the pivot means is subject to wear and the tremolo does not always return to its initial position. For the distance from the bridge elements to the anchoring points, there is an additional amount of unplayable string that is further subject to stretch. Where such demands on the tremolo are minimal this disadvantage is often traded-off for the advantage this extra length contributes as a “looser” feel in playing the instrument.
Improvements to the Fender U.S. Pat. No. 2,741,146 fulcrum tremolo have included using string clamps at the nut and immediately behind the intonation points on each of the bridge elements to limit string stretch to within these two points that define the scale length and separately adopting a novel beveled edge adjustably supported by two screw-like members positioned in the body at the fulcrum point to improve the return to initial position after pivoting the tremolo device (Rose U.S. Pat. No. 4,171,661). In Rose U.S. Pat. No. 4,497,236 a combination of the bridge elements, the tailpiece and fine tuners replaced the “novel bridge structure” incorporating the tailpiece of the Fender device and Rose U.S. Pat. No. 4,171,661 so that within the limited range (typically less than a whole tone) the strings could be re-tuned without unlocking the string clamps at the nut. However, string stretch beyond the range of the fine tuners necessitated a correction that is tedious and time consuming involving unlocking the string clamps, re-tuning the strings, re-adjusting the clamp, and re-tuning all the other strings to re-balance the equilibrium point back to initial position.
Therefore, for stringed musical instruments, as is known to those skilled in the art:                the second critical point is a clearly defined point on the bridge or individual bridge elements, the adjustment of which relative to the first critical point on the nut defines the length of the string or scale length and is called harmonic tuning; for fulcrum tremolos as originated by Fender U.S. Pat. No. 2,741,146, when pivoted:        both the bridge portions and the string anchoring means, the tailpiece, simultaneously move about a fulcrum axis;        there is a tendency for the harmonic tuning to be upset; and        various factors can disturb the equilibrium point between the tension of the strings and the tension of the counter springs and as a consequence disturb the initial position; and for those fulcrum tremolos equipped with fine tuners as with Rose U.S. Pat. No. 4,497,236, Storey U.S. Pat. No. 4,472,750 and Fender U.S. Pat. No. 4,724,737:        the fine tuners simultaneously move with the bridge and tailpiece portions about the fulcrum axis when the device is pivoted; and        fine tuners are designed to offer the tuning of the strings a minor adjustment of pitch after the general tuning is first achieved by the tuning pegs on the head of the instrument; and for those fulcrum tremolos fitted with string locks at the first and second critical points as in Rose U.S. Pat. No. 4,171,661,        string stretch beyond the clamps at the first and second critical points is eliminated offering the most stability of tuning possible for the set of problems associated with string stretch.        
In Steinberger U.S. Pat. No. Re. 31,722 stringed musical instruments without tuning pegs placed in the typical fashion on the head of the instrument were commonly known as “headless” stringed musical instruments. The replacement tuning machines were mounted on the body opposite the side where the neck joins the body.
In Takabayashi U.S. Pat. No. 4,608,905 describes an improvement on fulcrum tremolos incorporating “octave tuners”, tuners which functioned as the tuning pegs at the head of the instrument and as such integrated the tailpiece function in the tuning means. The bridge portion of the device comprised a “roller” configuration for the second critical point similar to Storey U.S. Pat. No. 4,742,750 and Steinberger U.S. Pat. No. 4,704,936. A cylindrical portion distanced from the bridge portion adjustably secured to the base plate houses a string holder member for one end of the string which is “fitted in such a manner as to be allowed to move freely in the axial direction”. The ball end of each string is arranged to be anchored “to the rear end opening of the string holding members” which is adjustably positionable “in the stretching direction of the strings for effecting octave tuning”. The string continues through the string holder member sufficient in size to ensure that the wrapping of the ball end does not extend over the second critical point and then passes on over the bridge element towards the nut. In this device the string holder member accomplishes the tailpiece function by anchoring the string at a single point which moves accordingly when the string holder member is displaced to achieve the tuning of the instrument.
Further improvements in the fulcrum tremolo utilized an arrangement with ball bearings at the pivot point within a housing adjustably mounted to the body which not only improved return to initial position after use of the tremolo but also virtually eliminated the wear and tear associated with prior art (McCabe U.S. patent application Ser. No. 07/607,458, Continuation No. 08/027,729, filed Jan. 14, 1993).
Additionally, the replacement of fine tuners with macro-tuners on a fulcrum tremolo (McCabe U.S. patent application Ser. No. 07/607,458, Continuation No. 08/027,729, filed Jan. 14, 1993) provided an intonation module that included a novel integrated one piece bridge-tailpiece structure secured to the base plate where each string anchored within its respective structure passes through a separate lever member and over the bridge element wherein the lever member could be displaced by an adjustment bolt to provide the means to bring and adjust the strings to playing pitch from an untensioned condition circumventing the re-tuning limits imposed by the fine tuner arrangements. These macro-tuners are often part of an intonation module dedicated to each string for use with but not exclusive to “headless” stringed musical instruments, that is, instruments without tuning pegs placed in the typical fashion on the head of the instrument. Certainly, a fulcrum tremolo with macro-tuners could be used with instruments which had tuning pegs without a disadvantage. Further, macro-tuners could be placed on the head or the body of the instrument and if integrated with a string anchoring means could replace the tuning pegs.
Macro-tuners refer to tuners with the capacity to raise and adjust the tension of the strings from an untensioned condition to a proper playing pitch, an as such provide for alternate tunings and compensation for substantial string stretch during the life of the string essentially without additional means.
Often the musician is called upon to play in an ensemble where the other instruments are not tuned to a typical concert pitch. Accordingly, the musician must flatten or sharpen the initial tuning of all the strings on his instrument in order to meet the pitch requirements of other instruments. This re-tuning often disturbs the initial position because the tension of the counter springs has not been readjusted as well. Accordingly, the position of the base plate of the tremolo is either tilting away from or towards the body of the instrument which then can limit the range in which the tremolo can be activated. Steinberger U.S. Pat. No. 4,632,005 and Gunn U.S. Pat. No. 4,955,275 provide for an adjustable counter spring and utilize an adjustment knob that provides a means to vary tension of the counter spring and thereby maintain the equilibrium point between the tension of the counter spring and the tension of the strings on fulcrum tailpiece tremolo, that is, a tremolo device where the bridge elements do not pivot with the anchoring means and, therefore, do not upset the harmonic tuning as such.
The “octave tuners” of the Takabayashi fulcrum tremolo U.S. Pat. No. 4,608,905 anchor the strings at a point on the string holder member spaced on the opposite side from the second critical point on the bridge elements. This arrangement presents serious problems for this tremolo device:                the length of the string subject to stretch beyond scale length, which includes the additional string length as measured from the bridge element to the anchoring point, is increased excessively in general at initial position and far more so when the device is pivoted in view of Rose U.S. Pat. No. 4,171,661 and,        tensioning of the strings which holds the ball end of the string securely against the rear end opening of the string holding member is inadequate to keep the ball ends as originally seated in initial position throughout the performance range of the tremolo; such mis-seatings are devastating to the effort to maintaining a tuned instrument.        